In a typical refinery, crude oils are subjected to atmospheric distillation to produce lighter fractions such as gas oils, kerosenes, gasolines, straight run naphtha, etc. Petroleum fractions in the gasoline boiling range, such as naphthas, and those fractions which can readily be thermally or catalytically converted to gasoline boiling range products, such as gas oils, are the most valuable product streams in the refinery. The residue from the atmospheric distillation step is then distilled at a pressure below atmospheric pressure. This later distillation step produces a vacuum gas oil distillate and a vacuum reduced residual oil which typically contains relatively high levels of asphaltene molecules. These asphaltene molecules are responsible for most of the Conradson Carbon Residue (CCR) and metal components in the resid. They also contain relatively high levels of heteroatoms, such as sulfur and nitrogen. These feeds have little commercial value, primarily because they cannot be used as a fuel oil owing to ever stricter environmental regulations. These feeds also have little value as feed-stocks for refinery processes, such as fluid catalytic cracking, because they produce excessive amounts of gas and coke. Also, their high metals content leads to catalyst deactivation. Thus, there is a great need in petroleum refining for greater utilization of such feed-stocks for example by upgrading them to make them more valuable cleaner and lighter feeds.
U.S. Pat. No. 4,214,977 discloses the slurry type process for conversion of heavy hydrocarbon oil using iron-coal catalyst of −100 mesh, in presence of hydrogen. The catalyst reduces the coke precursors and maximum conversion (525° C.) of 70% was obtained depending on reaction severity.
U.S. Pat. No. 5,374,348 discloses a slurry hydro cracking process in which the feed is converted to light hydrocarbon in presence of hydrogen and catalyst (iron-coal) having particle size 45 μm. The heavier fraction having boiling range (450+° C.) including catalyst (iron-coal) is recycled to the reactor thereby reducing the requirement of fresh catalyst addition by about 40%.
U.S. Pat. No. 5,755,955 discloses the improvement in hydroprocessing of heavy oil, obtained by recycling heavy fraction consisting of coke-inhibiting additive and maintaining high ratio of lower polarity aromatics to asphaltenes by adding aromatic oils to feedstock, which may be decant oil from a fluid catalytic cracker or heavy gas oil from hydrocracker or from waste material such as polystyrene waste.
U.S. Pat. No. 7,585,406 discloses a process and catalyst to produce lighter hydrocarbons from high boiling point residue with 95% conversion and no coke formation in the presence of catalyst and hydrogen. The catalyst, then extracted from the solid residue (boiling points >520° C.) after combustion of the same and the catalyst is subjected to reuse.
US20070158236 discloses bimetallic catalyst precursors are manufactured from a plurality of molybdenum atoms and a plurality of atoms of a secondary transition metal (e.g., one or more of cobalt, iron, or nickel). The molybdenum atoms and the secondary transition metal atoms are each bonded with a plurality of organic anions (e.g., 2-ethyl hexanoate) to form a mixture of an oil-soluble molybdenum salt and an oil-soluble secondary transition metal salt. The molybdenum and/or the secondary transition metals are preferably reacted with the organic agent in the presence of a strong reducing agent such as hydrogen. To obtain this mixture of metal salts, an organic agent is reacted with the molybdenum at a temperature between about 100° C. and about 350° C. The secondary transition metal is reacted with the organic agent at a different temperature, preferably between 50° C. and 200° C. The metal salts are capable of forming a hydroprocessing metal sulfide catalyst in heavy oil feedstocks.
US20090127161 discloses a process and apparatus is disclosed for converting heavy hydrocarbon feed into lighter hydrocarbon products. The heavy hydrocarbon feed is slurried with a particulate solid material to form a heavy hydrocarbon slurry and hydrocracked to produce vacuum gas oil (VGO). A light portion of the VGO may be hydrotreated and subjected to fluid catalytic cracking to produce fuels such as gasoline. A heavy portion of the VGO may be recycled to the slurry hydrocracking reactor. FCC slurry oil may be recycled to the slurry for hydrocracking.